Self-contained underwater breathing apparatus usually consists of a diving tank filled with compressed air or oxygen, which is strapped to the back of the diver so that the diver is independent of an external supply of air and is free to move about underwater without being impeded by hoselines. Although the diving tank is buoyant and essentially weightless underwater, it is quite heavy above water, often weighing over sixty pounds. As such, the diving tank is cumbersum to handle, carry and store.